Wenger: Arsenal was tracking Thauvin

The attacking midfielder starred at the Under-20 World Cup in the summer, scoring three goals to help France claim the trophy, and earned himself a move to Olympique de Marseille in the process.

However, there have been doubts over his temperament, highlighted by his refusal to train with former club Lille as he attempted to push through a big-money transfer to the Velodrome.

Wenger admits Thauvin's mentality is a cause for concern but says he is a big admirer of the 20-year-old's ability on the ball, revealing that Arsenal was tracking the youngster before he left Lille for Marseille.

"This transfer was a surprise for me. We were also following him, and we were interested in him before he went to Lille [from Bastia in January of this year]," he told reporters. "He is one of the great hopes of French football. He will go higher. He's only 20 years old.

"His progress does not depend on his talent, but I would say it depends on his mind. The future will tell [the story]."

Thauvin is expected to start for Marseille in Tuesday night's Champions League clash with Arsenal at the Emirates.